A conventional automobile three-stage steering lock, as shown in FIGS. 1-3, comprises an elongated body member 10, a lock housing 11, an elongated tube member 12, an elongated rod member 13, a locking means 14, a key lock 15, two locating means 16, 16' two coiled springs 17, 17' and a cap plate 18.
When the lock is to be applied on a steering wheel, a hook 101 in the body member is to be engaged with a steering wheel and then a hook of the elongated tube member 12 is to be engaged with the steering wheel and the elongated rod member 13 is to be telescoped freely within the body member 12 outward to a corner where a windshield and a car door meet. Meanwhile the locating means 16, 16' can slide along on the longitudinal surface of the rod member 13 and finally stop to fit in one of annular grooves in the rod member 13 to lock it immovable at a needed length, preventing the steering wheel from being turned around. Under this condition, the springs 17, 17' elastically push down the locating means 16, 16' so that the bottom ends 160, 160' of the locating means 16, 16' fit in one of the annular grooves of the rod member 13, keeping the rod member 13 from being pushed inward within the body member 10.
But the chances are that the tube member 12 and the rod member 13 can be completely pulled out of the body member 10 if they should be pulled with excessive force, and consequently they may hurt a user or a car window. Besides, if the lock should be held with the outer end of the rod member 13 down and the outer end of the body member up, the rod member 13 and the tube member 12 would easily slip out of the body member 10 because of their own weight.